1. Field of the Invention
The present invention concerns a washing, bleaching and cleaning product that is particularly suitable for use at lower temperatures. The invention is particularly concerned with such products that comprise as bleaching agent an alkalimetal monopersulphate and as activator therefor an alkalimetal halogenide.
2. Description of the Prior Art
The published German patent application DAS No. 1,144,675 describes washing, bleaching and cleaning products comprising an alkalimetal monopersulphate and an alkalimetal halogenide. According to this publication halogen ions improve the bleaching action that is obtainable by means of the alkalimetal monopersulphate. This improvement is achieved by the addition e.g. of sodium chloride as the halogen-ion releasing compound.
The improvement of the bleaching effect is however not very marked and the object of the present invention is therefore to improve significantly the bleaching efficiency of the alkalimetal persulphates, in particular at lower temperatures.
U.S. Pat. No. 3,458,446 describes a scouring product which comprises an alkalimetal monopersulphate and a water-soluble bromide as activator therefor. According to this specification the addition of the bromide ensures a bleaching powder on hard surfaces that is far superior to that obtained by means of chloride.
On studying the alkali monopersulphate/alkali bromide system for bleaching fabrics, which is an application that is not mentioned in U.S. Pat. No. 3,458,446, it has been found that incorporating a bromide as activator for an alkalimetal monopersulphate does significantly improve the bleaching power on fabrics but simultaneously causes completely unacceptable damage to the fibres.
The object of the invention is therefore to provide a solution for the problem of the disadvantage of the damage to the fibres on using an alkalimetal monopersulphate as bleaching agent and a compound supplying bromide ions as activator for the alkalimetal monopersulphate.
According to the published German patent application DAS No. 1,221,752 it is known to add to an alkalimetal monopersulphate/alkalimetal chloride system a nitrogen-containing compound acting as chloride-hypochlorite acceptor. This system however contains an alkalimetal chloride in such an amount that particularly when in solution at a pH of 0-8 an undesirable amount of chlorine is released which is taken up by the nitrogen-containing compound. The amount of alkalimetal chloride used according to the published German patent application varies from 1 to 10 times the amount of alkali monopersulphate, whereas the small amount of alkali bromide according to the invention is considerably smaller.